Bit holder for coal-cutting chains



Jan. 11, 1949.

E. F. JOHNSTON` BIT HOLDER FOR "COAL CUTTING HAJNS F1144 Aug. 28, 1945 Patented Jan. 11, 1949 UNIT-ED sfr-A11*i375.

2,45s,lc" n z BIT HoLDEa'FoR COAL'JTINQ f "Edwin Ff-Johnston,Eaningtoiisirysf, Application August 28, 'rszrill My invention relates to improvementsinfcoalm vcutting chains and has for its obiect tot'prov'ide a bit holder so formed as to permit rapid release for a cutter bit.

A further object of this invention is to provide means whereby a bit may be very rapidly inverted or renewed in the holder.

Another object of this invention is to provide means in a bit holder for maintaining the holder lugs against movement in reversal of the coal cutting chain.

Other features and advantages will become more readily apparent from the following description and the accompanying illustrative drawings in which:

Figure 1 is a plan view of a chain link embracing my invention,

Figure 2 is a sectional elevational view thereof,

Figure 3 is a sectional view taken on line 3-3 of Figure 2,

Figure 4 is a perspective View of a pair of bit holding lugs shown separated, and

Figure 5 is a fragmentary elevational view of a coal cutting chain. In the accompanying drawings as above enumerated and in the following specication, like characters of reference indicate like parts throughout and in which I0, indicates my in-v vention which comprises a chain link II-, having an upstanding portion I2, provided with an arcu- 30 ately formed pocket I3, in which is seated a pair of similarly formed lugs I4 and I5, the lower ends I6 and I1, of which are provided with disconnectible hinge members I8 and I9. In the central upper portion 20, of lug I5, is provided a half-diamond shaped recess 2I, in which is seated the lower portion 22, of a diamond-shaped cutter 23, which is removably held in the recess 2I, by the overhanging portion 24, of the lug I5, said overhanging portion being provided with a slot 25, into which the portion 26, of the cutter 22, is adapted to project when the members I4, I5 and 22, are in operative position, the point 2l, of the cutter projecting outwardly of the member I2, to cooperate with other cutters 22, 28, 29, etc., of the chain 30. The arcuate wall 3I, of the member I5, is provided with a series of ratchet teeth 32, into which the dog 33, pressed by a spring 34, is adapted to seat in order to hold the member I5, in rearward position when it is desired to remove or change the position of the said cutter, either end of which may be projected for cutting operations. 'I'he stem 35 (shown dotted), has pivoted thereto a cam 36, with a lever handle 31, for operation 'forthe removal o'fithe members Wand lyfrom lthe said reces pockety I3.l Thellinks" II, H",

etes areprovlffwithftheusuai bores as anzi-sa,

whereby said links may be connected in the usual manner.

It is thought that persons skilled in the art to which the invention relates will be able to obtain a clear understanding of the invention after considering the description in connection with the drawings. Therefore, a more lengthy description is regarded as unnecessary.

Changes in. shape, size and rearrangement of details and parts such as come within the purview of the invention claimed may be resorted to, in actual practice, if desired.

Having now described my invention that which I claim as new and desire to procure by Letters Patent is:

1. A chain link having an outwardly projecting block provided with a substantially cylindrical recess, a pair of lugs which combined have their surfaces conforming to the walls of the said recess and adapted to hold a bit, one of the lugs provided with a pocket shaped to conform to the contour of a substantial portion of the bit, said lugs having slip hinge connections at their lower ends, the other lug having a protruding upper edge provided with a socket into which an edge of the bit is adapted to proj-ect and whereby the said bit is locked within its seat, means whereby the lugs may be held against movement, a ratchet formed on the outer wall of one of the lugs and a spring controlled dog adapted to engage the ratchet teeth and forming said locking means, and means for holding the dog from engagement with the ratchetteeth.

2. A chain link havingan outwardly projecting block provided with a substantially cylindrical recess, a pair of lugs which combined have their surfaces conforming to the walls of the said recess and adapted to hold a bit, one of the lugs provided with a pocket shaped to conform to the contour of a substantial portion of the bit, said lugs having slip hinge connections at their lower ends, the other lug having a protruding upper edge provided with a socket into which an edge of the bit is adapted to project and whereby the said bit is locked within its seat, means whereby the lugs may be held against movement, and a ratchet formed on the outer wall of one of the lugs and a spring controlled dog adapt-ed to engage the ratchet teeth and forming said locking means 3. A chain link having an outwardly project- 4 ing block provided with a substantially cylindrithe other lug having a protruding upper edge cal recess forming camming surfaces, a pair of provided with a socket into vvhich an edge of the lugs which combined have their surfaces conbit is adapted to project for locking the bit within forming to the walls of said recess for camming its seat, an arcuate cam rack on the lug formed action to hold a bit, one of the lugs provided 5 with the bit-receiving pocket, and a cam rewith a pocket shaped to conform to the contour tractable spring-projected detent supported by of a, substantial portion of the bit, said lugs said block and engageable with said cam rack having slip hinge connections at their lower ends, for preventing the removal of said lugs from the the other lug xhaving a protruningruppem edge mcylindrical recess in said block. provided-with asocketfinto Whichan-edgefof the 10 'EDWIN F. JOHNSTON. bit is adapted to project and whereby the said bit is locked Within its seat, and resiliently tensioned REFERENCES CITED means for preventing thefremoval ofisadlugs i',Thefollowing-.references are of record in the from the cylindrical recess in said'block. me of this ptent:

4. A chain link having an outwami'lyfpr'ojectfI 1115 Y ing block provided with asubstantiallycylin- UNITED STATES PATENTS drical recess formed with camming surfaces, a Number Name Date pair of lugs which combined have theinzsuraces f-::989;674 Weiss Apr. 13, 1911 comforming to the Walls of said recess and 1,677,950 Bowman"` July 24, 1928 '.adaptedto huida-bit, one-Ofi thermes, provided 2o m5191804 f1. stenger etai.v Mar. 10, 1931 rwith aepockenshapedzto conform-.to-,thecontour 2,036,327 ,f-Eulke Apn v7, 1936 ofv a isubstantial portionsl-of the-bitf said Mlugs having slip hingeconnections. attheiriower ends, 

